Kimura Masatomo
Department of Pathology, Kinki University School of Medicine, Osaka-Sayama, Osaka, Japan.
Nihon Ishinkin Gakkai Zasshi. 2008;49(4):269-73. doi: 10.3314/jjmm.49.269.
A pathological diagnosis can be a decisive diagnosis for deep-seated mycosis. HE stain is used to look for structural changes of the infected lesion and then various special stains are used to visualize the fungus in sections. When viability of the fungus is low, it is faintly stained with HE or PAS. Grocott stain can clearly demonstrate the fungus regardless of viability. Overstaining and understaining sometimes occur. Grocott stain is not suitable to detect structural changes of an infected lesion. Cell walls of Cryptococcus and dematiaceous fungi are stained brown with Fontana-Masson stain because of the existence of melanin. However, it is noteworthy that some Aspergillus and zygomycetes also turn brown with this stain. Fungiflora Y with a fluorescence microscope can readily demonstrate most fungal hyphae except zygomycetes. Immunohistochemistry with antibody against various fungi and in situ hybridization are useful to confirm a fungal genus on paraffin sections. Furthermore, probes to detect specific species of Aspergillus for in situ hybridization are now available.
病理诊断对于深部真菌病可能是决定性的诊断。苏木精-伊红（HE）染色用于观察感染病灶的结构变化，然后使用各种特殊染色来在切片中显示真菌。当真菌的活力较低时，它在HE或过碘酸希夫（PAS）染色中染色较淡。格罗科特（Grocott）染色无论真菌活力如何都能清晰显示真菌。有时会出现染色过度和染色不足的情况。格罗科特染色不适合检测感染病灶的结构变化。由于黑色素的存在，新型隐球菌和暗色真菌的细胞壁在Fontana-Masson染色中染成棕色。然而，值得注意的是，一些曲霉属和接合菌在这种染色下也会变成棕色。使用荧光显微镜的真菌荧光染色剂Y可以很容易地显示除接合菌外的大多数真菌菌丝。用针对各种真菌的抗体进行免疫组织化学和原位杂交有助于在石蜡切片上确认真菌属。此外，现在有用于原位杂交检测曲霉属特定菌种的探针。
